Yeap, the current owners of Gamespy, IGN, decided to shut it down a while back and the most famous titles with big publishers are switching or have already switched to Steamworks (such as Borderlands). Others are still in limbo until May 31, such as pre-Origin Battlefield games, with the publishers "considering" finding an alternative. But most of the old games will just be lost like tears in rain...
Same thing is happening with Games for Windows Live
edit: ...
and EA just confirmed that they will be shutting down old Battlefield games on June 30